A measure of dispersion will tell you how varied or spread out the scores are in a data set.
The standard deviation shows us how spread out the scores are from the mean. It is calculated by finding the square root of the variance.
Amy probably chose to calculate the standard deviation because she thought she was working with interval data. As the participants gave a score from 1 to 100 regarding how much f a problem they though homelessness was in their country this isn’t really in standardised units and therefore she might have been better to look at the range or the interquartile range which can be sued with ordinal data.
Amy can conclude that the people from the Czech Republic have much more widely varying views about the extent to which homelessness can be seen as a problem in their country as their SD of 86.7 is much larger than the SD for the people in China where the SD was 60.4, although this too is a very much figure again suggesting a good degree of variation in terms of opinion on this question.